Auxiliary battery



FIG. 1 is a perspective view of an auxiliary battery showing my new design.

FIG. 2 is an end elevational view thereof, the opposite end elevational view being a mirror image;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof. 

The ornamental design for an auxiliary battery, as shown and described. 